Association between Screening for Osteoporosis and the Incidence of Hip Fracture

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

Neil R. Powe, MD, MPH, MBA

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

Michael A. Levine, MD

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

Annette L. Fitzpatrick, PhD

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

Tamara B. Harris, MD, MS

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

John Robbins, MD

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

Linda P. Fried, MD, MPH

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

From Robert Wood Johnson Clinical Scholars Program, Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; University of Washington, Seattle, Washington; National Institute on Aging, Bethesda, Maryland; and University of California, Davis, Sacramento, California.

Acknowledgments: The authors thank Leon Gordis, MD, DrPH, for his thoughtful review of the research proposal.

Grant Support: The Cardiovascular Health Study was funded by the National Heart, Lung, and Blood Institute (contracts N01-HC-85079 through N01-HC-85086, N01-HC-35129, and N01-HC-15103). For a full list of participating CHS investigators and institutions, see 128.208.129.3/chs/pi.htm. The bone density scans were funded by the National Institute on Aging (intra-agency agreements Y02-AG-4-0251 and 1-Y02-HC-40205). Dr. Kern (maiden name, Korn) was supported as a fellow in the Robert Wood Johnson Foundation Clinical Scholars Program at the time this study was conducted. Dr. Powe is supported in part by the National Institute of Diabetes and Digestive and Kidney Diseases (grant K24DK02643).

Bone density scans (dual-energy x-ray absorptiometry [DEXA] at the hip) for participants in California and Pennsylvania (n = 1422) and usual care for participants in Maryland and North Carolina (n = 1685).

Results:

The incidence of hip fractures per 1000 person-years was 4.8 in the screened group and 8.2 in the usual care group. Screening was associated with a statistically significant lower hazard of hip fracture than usual care after adjustment for sex and propensity to be screened (Cox proportional hazard ratio, 0.64 [95% CI, 0.41 to 0.99]).

Limitations:

The mechanism of the association was unclear. A small unmeasured confounder that decreased the hazard of hip fracture could diminish or erase the observed association.

Conclusions:

Use of hip DEXA scans to screen for osteoporosis in older adults was associated with 36% fewer incident hip fractures over 6 years compared with usual medical care. Further research is needed to explore the mechanism of this association.